Automatic telephone-exchange apparatus.



G. E. KIMBALL.

AUTOMATIC TELEPHONE EXCHANGE APPARATUS. APPLICATION r1110 NOV. 24. 1906.

- Patented Apr. 4, 1916.

2 SHEETS-SHEET 1- I 6? a" ECZ'iraEaZZ W- $11.

Af0fl%.

G. E. KIMBALL. AUTOMATIC TELEPHONE EXCHANGE APPARATUS.

APPLICATION FILED NOV. 24. 1906.

Patented Apr. 4, 1916. E

2 SHEETS-SHEET 2 O\\\\\\\\\\\\\\\\\\\ O\ Q ER ducing the automatic step-by-step operation GEORGE E. KIMBALL, or CHICAGO, ILLINOIS, ASSIGNOR, EY MEsNE' ASSIGNMENTS, To EIEST TRUST AND SAVINGS BANK, TRUSTEE, or CHICAGO, ILLINOI Specification of Letters Patent.

Patented Apr. 4, 1916.

Application filed. November 24, 1906. Serial No. 344,813.

To all whom it may concern Be it known that I, GEORGE E. KIMBALL, a citizen of the United States of America, and resident of Chicago, Cook county, Illinols, haveinvented a certain new and useful Improvement in Automatic Telephone Ex change Apparatus, of which the following 1s a specification. My invention relates to interrupters, and more particularly to interrupters for proof a selectorthat is to say, the step-bystep operation by which a telephone selector switch finds an idle trunk line for a calling subscriber. An object of my invention is to provide an improved and highly eflicient interrupter.

Another object is to provide certain fe atures of improvement and details of construction and combinations tending to mcrease the general efliciency of an automatic or semi-automatic telephone exchange sys- .tem.

To the foregoing and other useful ends, my invention consists in matters hereinafter described and claimed.

In the accompanying drawings, Figure 1 illustrates diagrammatically a group of switches and an interrupter for operating said group.- Fig. 2 is a perspective diagrammatic illustration of a trunk selector switch Similar to the one disclosed in United States Letters Patent No. 815,321, granted March 13, 1906, to Keith, Erickson and Erickson.

The batteryB may have its positive terminal grounded. The magnetv H, say of sixty ohms resistance, isshown connected to my interrupter device A, by Way of the conductor 32 and switch wiper 2', to the conductor 2. Now when the switch 2" is closed onto the contact point 30 an energizing circuit is closed through the relay 3. Said circuit extends from groundG through the winding of the relay 3, conductor 2, contact point 30,

switch 2', conductor 32, through the winding of the magnet H to the battery lead 4:, thence through battery B and to ground G. Though the magnet H is in series with the relay 3 the former does not operatively energize, since the winding of the relay 3 is of high resistance, and consequently the current-flow is not sufficient to operate the comparatively low-wound coil H. The relay 3 upon energization attracts its armature 5, which operates to place the springs 6 and 7 in engagement. The engagement of said sprlngs closes an energizing circuit throu h the relay 8 extending from ground 2' through the springs 6 and 7, through the winding of the .relay 8 to the battery lead 4, thence through battery B and to ground G. The relay 8 upon energization attracts its armature 9, which operates to place the springs 10 and 11 in engagement, whereby the relay 3 becomes short-circuited and a new energizing circuit is established through the magnet H for operating the latter. This energizing circuit extends from ground Gr through the Springs 10 and 11, conductor 12 and conductor 2, contact point 30, switch 2:, conductor 32, winding of the magnet H to battery lead 4, thence through battery B and to ground G. The short-circuit of the relay 3 extends from ground G through the winding of the said relay, conductor 12, springs 11 and 10 to the ground G Accordingly the relay 3 den'erg'izes and the springs 6 and 7'disengage, thereby breaking the energizing circuit through the relay 8. The relay 8 in turn deenergizes and the springs 10 and 11 disengage, .thus breaking the energizing circuit through the magnet H' and removing the short-circuit of the relay 3. As soon as the short-circuit is removed from the relay 3 an energizing circuit is established, as before explained, and again the relay 3 operates to close the energizing circuit through the relay 8, which in turn closes the springs ,10 and 11 in contact, thereby again estab lishing the energizing circuit through the. magnet H, short-circuiting the relay 3. The

magnet H is thus intermittently energized for any purpose, while the switch '5 engages the contact point 30. The. frequency of the energization of the magnet H may be varied within certain limits by varying the tension of the spring 6. For instance, when the spring 6 is weak the operation is slower than when the said spring is stiff. Furthermore, the condenser 13 is provided to reduce the sparking when the springs 10 and 11 disengage. My interrupter may be employed to interrupt any circuits for signaling, lamp flashing, sign flashing, etc. Suppose, for example, that it is desired to intermittently energize the rotary magnet H of the selector I the said patent.

the said patent would correspond to or be switch disclosed in said selector patent. My

interrupter may be used, therefore, in connection with-the said selector by removing the old interrupter springs thereof, and by connecting the rotary magnet shown in said patent directly to the wiper 2', connecting the conductor 2 to the contact point 30 of The side switch wiper of the same as the side switch wiper i, and the contact points allotted to said wiper will correspond to the contact points allotted to the herein described wiper i The magnet H would, of, course, be the rotary magnet of the patent. The interrupted operations of the rotary magnet in the patent would then take place in the mannen-deseribed in connection with the magnet H. The armature h of the magnet H will, of course, correspond to the rotary armature of the rotary magnet of the said patent.

The relays drawings may be wound to any suitable re sistance, but with a battery B of fifty volts good results are obtained when the relay 3 is wound to a resistance of thirteen hundred ohms, and the relay 8 wound to a resistance of five hundred ohms.

The private magnet switch '5 of the selector is, of course, automatically opened as soon as an idle trunk line or trunk is found by the wipers of the selector. In this way the operation of the relays is continued, by the energizing of'ithe private magnet of the selector, until said priv'ate magnet is de energized when the wipers of the selector move onto idle or non-busy contacts.

My improved interrupter can be used individually, one to 'each selector ,or other switch, when used in an automatic or semi automatic telephone system; but as indicated in Fig. 1, my interrupter may be used in connection with a group of switches. The rotary magnet H of a second-selector switch corresponds to the rotary magnet H, and the side switch wiper T of the switch'to which the rotary magnet H belongs corresponds to the side switch wiper i Said side switch wiper T is, of course, also controlled by a private magnet, in the same manner as pointed out in connection-with the side switch wiper i of the other selector; and when the side switch passes to third position the interrupter circuit for the particular rotary magnet H is broken. Of course, the energizing circuit for the rotary magnet H would be the same as the one for the rotary magnet H, with the exception that it ineludes the contact point 30, the side switch wiper T and the rotary magnet H. In other words, a group of trunk selectors or other switches may be operated by one interrupter, which latter is, of course, normally at rest. One of these selectors, as already stated, is shown in Fig. 2. The line relays shown in the accompanying the vertical magnet 18. This vertical magnet, through the medium of the usual mechanism, raises the shaft 19 for the purpose of carrying the switch. shaft wipers 20, 21 and 22 opposite some particular group of trunk-lines, which trunk-lines terminate in the terminals of the banks 23. After the wipers have been thus raised the rotary line relay 15 is operated to energize the usual private magnet 24 which, by attracting and releasing its armature, permits the side switch O- to trip to second position, whereby the side switch wiper 2' (Fig. 1) is carried into'engagement with the contact point 30. This contact is connected with the interrupter relays by the conductor 2 through which the proper impulses are transmitted to the rotary magnet H and thence to the battery lead 4, and through battery B to ground G. It is evident that after the circuit is closed for the rotary magnet H this magnet H is'given impulses as long as the side switch wiper i is in engagement with the contact point 30, whereby, through the usual mechanism, the shaft 19 may be rotated and the shaft wipers advanced into engagement with any particular set of trunk terminalsend, therefore, with the corresponding trunk-line. If the shaft has been raisedto the second level, for example, it will be-unders tood that if the first trunk is idle the rotary magnet H will receive only one impulse, because the armature 25 of the rotary magnet will operate the armature 26 of the private magnet, which on returning to normal will cause the side switch to 'be tripped to third position. However, if the first trunk is busy the private wiper 22 will be carried into engagement ,1 with a grounded contact (the first private bank contact of the second row), whereby an energizing circuit is established through the private magnet 24:. This private magnet willthen attract its armature 26 before the rotary armature 25 has time to fall back, and will hold this armature 26 down even after the rotary armature 25 has'operated for the first step, thereby retaining the side switch in second position until the rotary magnet H receives another impulse from the conductor 2. (See Fig. 1). Of course, the shaft 19 willthen be rotated a second step, and if the next trunk is idle the energizing circuit through the private magnet 24 will be broken, which private magnet will then abandon the armature of the private magnet to the rotary armature 25, which rotary armature will operate as in the first instance to allow the private magnet armature to trip the side switch to third position. It will be understood, however, that the private magnet 24 will be retained energized as long as the private wiper 22is carried into engagement with the grounded contact.

The selector switch is provided with the usual release magnet,27 which may be energized in the usual manner for restoring the switch after a connection has been made with the trunk-line.

i 25 release magnetis denergized.

What I claim'as my invention is 1. An interrupter comprising a pluralityof mutually or reciprocally controlled relays,- and step-by-step switching means having a magnet included in the energizing circuit of one of said relays and responsive to the interrupted current thus produced.

2. The combination of a first relay, a second relay, means by which the energizing of the first relay energizes the second relay, means by which the energizing of'the second relay deenergizes the first relay, a magnet intermittently energized by the successive energizing and deenergizing of said relays,

'40 said magnet included in the energizing circuit. of. the" first relay, and step-by-step switching means operated by the said magnet. 3. The combination of a first relay, a

second relay, means by which'the energizing of the first relay energizes the second relay, means by which the energizing of the second relay short-circuits or shunts the first relay,

' a magnet, intermittently energized bythe successive energizing and deenergizin'g of said relays, said magnet included in the energizing circuit of the first relay, and step-by-step switching means operated bycircuiting the latter, whereby the magnets are energized.

the said magnet. I 4;. The combination of a first relay,; a

second relay, an energizing circuit for said first relay, means for closing said circuit, means by which the energizing of the first relay energizes the second relay, a normally open connection bywhich theenergizing of the second relay short-circuits or shunts'the first relay, a magnet intermittently energized by the successive energizing and deenergizing of said relays, said magnet included in the energizing circuit of the first relay, and

step-by-step switching means operated by the said magnet.

5. The combination of a first relay, a second relay, means by which the energizing of the first relay energizes the second relay,

means by'which the energizing of the second relay deenergizes the first relay, a magnet "intermittently energized by the successive energizing and deenergizing of said relays, a plurality of trunks, a trunk-selecting switch mechanism operated by said magnet,

said magnet included in the energizing circuit of the first relay, and automatic means for stopping the operation of said relays when an idle trunk is found.

6. The combination of a first .relay, a second relay, means by which the energizing of the first relay energizes the second relay,

means by which the energizing of the second relay short-circuits or shunts the first relay, a magnet intermittently energized by the successive energizing and deener'gizing of said relays, a plurality of trunks, a trunk-- selecting switch mechanism operated by said 'magnet, said magnet included in the ener-' gi'zing circuit of the first relay, and automatic means for stopping the operation of said relays when an idle trunk is found.

7. The combination of a first relay, a

second relay, an energizing circuit for said first relay, means for closing said circuit, means by which thevenergizing of the first relay energizes the second relay, a normally open connection by which the energizing of the second relay short-circuits or shunts the first relay, a magnet intermittently ener-. gized by the successive energizing and deenergizingof said relays, a plurality of trunks, a trunk-selecting switch mechanism operated by said magnet, said magnet included in the energizing circuit of the first relay, and automatlc means for stopping the operation of said relays when an idle trunk is-found.

8. In a telephone system, a plurality of automatic switches, each switch provided with an operating magnet, and an interrupter common to said switches, said interrupter having a relay adapted to .be Qner-i gized in series with any one of said magnets, the resistance of said relay being sufficient to prevent energizing of said magnets, and means controlled by said relay for short- 9; In a telephone system, an automatic switch provided with an operating magnet,

relay adapted to be energizedin series with high resistance to prevent energizing of said magnet, and means controlled by said relay for short-circuiting the winding thereof, whereby the magnet is energized.

10. In a telephone system, an automatic switch provided with an operating magnet, and an interrupter for controllingthe op eration of said switch, said. interrupter pro vided with one relay adapted to be energized in series with said magnet, said relay being of suflicient resistance to prevent energizing of said magnet, a second relay controlled by said first-mentioned relay, and means conrmami trdlled by said second relay for short-cir- 10 cuiting the first relay, whereby the latter is denergized and the said magnet energized. Signed by me at Barberton, Summit county, Ohio, this 15th day of Now, 1906. GEORGE E. KIMBALL. Witnesses:

A. A. MOORE, .13. M. WELLER. 

